Recommended Posts

I read that article many years ago, and in some cases, it can be applicable. Keep in mind that you are also driving essentially a dummy resistor load, and the results may be different driving a reactive load, where back EMF is reflected on the power supply.

I'm sure someone could find an application for this, but the more I think about it the less it seems worth the hassle. Wouldn't it be easier to series the load and use the amp in bridged mode like you normally would, and skip the parallel inputs and reversing the polarity on one of the outputs?

Even in the best case scenario of a 15% gain, we're talking about a fraction of a single dB of gain.

Share this post

Link to post

Share on other sites

I'm sure someone could find an application for this, but the more I think about it the less it seems worth the hassle. Wouldn't it be easier to series the load and use the amp in bridged mode like you normally would, and skip the parallel inputs and reversing the polarity on one of the outputs?

Even in the best case scenario of a 15% gain, we're talking about a fraction of a single dB of gain.

The real answer is it depends. I agree that it may only be a small fraction of a difference. It would be interesting to note the input power to the amplifier to see if the efficiency / breaker utilization changes any, which may be a bigger deal for large systems with racks and racks of amplifiers running off a generator, or in a venue where power is subject to droop. ( older wiring, smaller services )

The basic theory is that if an amp is driven in stereo and both channels are producing the exact same signal, both channels are also drawing current from the power supply at the exact same time/interval. The author of the article claims that if you parallel the inputs but flip the polarity on the input of one of the channels, causing the sine waves from each channel to be exact opposites, the channels are now "taking turns" drawing current from the power supply.

This is how Powersoft K series amps operate all of the time. Those guys are smart so you'd have to assume they did that for a reason. This likely only shows up as a measureable improvement when the power draw becomes large and starts to sag the AC line. More useful for pro sound apps where you might have many amps driven hard on one circuit and/or the circuit isn't great to begin with like a generator, etc.

Many years ago Ivan Beaver from Danley Sound showed me how to do this at a GTG. Flip polarity of one input channel in the amp and re-flip/correct at the speaker wiring to bring back in phase. Worked pretty good with a Crown CE4000.

I am Justin Ryan, CEO of SpeakerPower. In 2018, I acquired SpeakerPower from its founder, Brian Oppegaard, upon his retirement. I am very excited to continue the growth and development of SpeakerPower. As an experienced executive in a variety of industries, and an MIT trained engineer, I know what it takes to develop exciting new products that satisfy the most demanding requirements of customers for their cutting edge products. With further investment in new products, I plan to build on SpeakerPower's 16 year track record of delivering high quality, powerful, efficient, and intelligent amplifiers.

For OEM manufacturers in Professional and Home Theater markets, SpeakerPower provides the opportunity to have next-generation intelligent amplifiers in your self-powered loudspeaker line. Our complete turn-key approach means that it is as easy for you to install a SpeakerPower amplifier in your cabinet as a woofer, horn or compression driver. With our proven designs, you will be up and running quickly with minimal up-front investment. And our state-of-the-art digital signal processing and power technology will reinforce your image as a technological leader. With designs from 200 to 12,000 watts, we can meet your most critical needs.

Users of SpeakerPower amplifiers enjoy high power and high efficiency, with intelligence designed to ensure continuous output in the most demanding applications. Our products are manufactured and supported right here in California. Our commitment to quality, technological acuity, and steadfast product support means your loudspeakers are powered with confidence. See what we can do for you today.

Share this post

Link to post

Share on other sites

Yep...I emailed Brian about the SP1-6000 plate amps a few weeks ago and he put me in contact with Justin. Brian says he still does consulting work for SP when needed but otherwise is retired.

Someone over at AVS received an sp1-4k or 6k recently and looks like they are using an internal cover again on the plate models. Glad to hear Brian's potentially still got some input there even if he does spend most of his time sitting on a beach drinking rum now.

Share this post

Link to post

Share on other sites

Someone over at AVS received an sp1-4k or 6k recently and looks like they are using an internal cover again on the plate models. Glad to hear Brian's potentially still got some input there even if he does spend most of his time sitting on a beach drinking rum now.